But I forgot. It's never the poor bikers fault around here. There too busy saving the planet from the evil car drivers and twisting facts to their best advantage. Barring that, they just drift away from the conversation like ti never happened.

I seem to have read a number of comments on here how bikers think the only way they can gain any respect is by doing a little destruction. Sounds like this biker is one of that group.

The car driver is a dangerous lunatic but there had to be a little something more than a verbal altercation to for him to crack this badly.

Anon, I am merely pointing out that you leaped to a conclusion on the say-so of a deranged person. Most people run when chased by a nut in a car, so we can't really learn anything from that, either.

What we do know, is that someone in a car, certainly broke the law, and endangered a bunch of people, and tore up public property. For that, we have multiple sane witnesses.

If the nut had been on a bicycle instead, it would have been safer for everyone else, and probably would have done less damage to the park. Bikes are better, even in the hands of lunatics (perhaps, especially in the hands of lunatics). (We know this, because of laws of physics, and accident statistics.)

And similarly, if I were angry at a driver, I would be unable to quickly release my u-lock (takes 2 hands), never mind my intent -- does that mean that I therefore conclude that the U-lock story is a lie, because I personally would not and also could not whack the mirror with my lock?

What you or I would do, does not necessarily determine what happened here. Some people carry their U-locks at the ready. Some people don't trust the police very much.

Nonetheless, I think you are probably right, but your certainty annoys me. The only information about the bicyclist that we have, comes from a proven nutjob, and from that, you certainly conclude that the cyclist did thus-and-such. That's unwise, and also a little insulting; you're clearly willing to believe the worst of an unknown cyclist, whereas I don't put complete faith in the word of a proven nut. He could be lying -- perhaps he accidentally or intentionally squeezed the cyclist against parked cars, such that the only choice the cyclist had was to run into his mirror (no u-lock, no fault of the cyclist). Perhaps he nicked the mirror on a tree, chasing a guy who insulted him. I once had a nut return to run me off the road after I flipped him off; a friend, hit and hurt by a car, had the nut return to lecture him on "safety"; there was that doctor in California who swerved and braked hard in front of two cyclists coming down a hill. A guy who would leave the road to drive through a park full of people, he might also lie, too.